Ever since the advent of glass lined commercial water heaters in the early 1960s, water heater end users as well as water heater manufacturers have sought methods of increasing the lives of glass lined tanks. Although the life of glass lined tanks is longer than galvanized tanks previously used, the savings have been more than offset by the higher initial costs for the water heaters brought about by new safety and efficiency requirements mandated by some states as well as the Federal Government.
To ensure that water heater tanks will last through the warranty periods all manufacturers install anodes in the tanks. Anodes for water heater tanks can be magnesium, aluminum, or zinc. The anode is a sacrificial rod that coats bare areas that may exist or come to exist within a water heater tank as glass erodes in a normal attrition process. As anodes coat the bare areas in the tanks they become depleted. Once the anodes are depleted the tanks are destined to fail in less than a year. For this reason many people desire to extend the lives of the tanks by replacing the depleted anodes after the tank warranties expire.
In an effort to convince end users that they can extend the lives of the water heater tanks beyond the warranty periods, manufacturers make some of the anodes somewhat accessible. Anodes have been made accessible in the top of the tanks so that consumers can replace anodes if they desired to do so. Anode suppliers also offer link type anodes to be inserted in fittings on the side walls of the tanks near the tops of the tanks. However, very few tanks have these extra fittings. When the tanks do have them, the fittings are usually inaccessible once the water heaters are installed.
To also ensure that tanks will last through the warranty period, all manufacturers install hand hole cleanouts so that the excessive lime that builds up in the tanks can be removed. All manufacturers now require that the hole clean out plates which are easy to remove and re-install, be removed so that the lime and sediment build up can be removed from the tanks on a regular basis.
While providing access to some of the anodes for replacement has helped a small number of end users, it has not been of significant help to most end users due to the fact that the anodes are very difficult to remove after the water heaters are in service for a few years. Prior to the present invention, there has been no way to install replacement anodes in many of the existing water heater tanks without completely disconnecting the entire water heater and then disassembling the vents, jacket tops and often the flue collectors because the anodes are often located underneath the flue collectors. Removing the flue collectors to replace anodes is a major task and in most cases it is extremely difficult to do so without damaging the water heaters and rendering them unsafe.
After disassembly has been accomplished, the user must then attempt to remove the old anodes. In most cases the anodes cannot be removed because of corrosion of the fittings. People attempting to replace the depleted anodes also often damage the flue collectors and flue collector sealants. Consequently, the end users cannot replace the anodes without hiring plumbing contactors and in many cases even the plumbers cannot remove depleted anodes and replace them with new anodes.
For these reasons people are resigned to the fact that they cannot replace the anodes on most of the most expensive commercial water heaters in the field today and they no longer attempt to do so without calling a professional plumbing company that specializes is such work and even these companies cannot remove and replace many of the anodes. This professional service also costs too much to make it a practical solution As a result, most of the more expensive commercial water heaters fail several years sooner than they would if replacement anodes could be installed.